diff options
| author | Alex Ivanov <gnidorah@p0n4ik.tk> | 2013-09-20 17:36:06 +0400 |
|---|---|---|
| committer | Alex Deucher <alexander.deucher@amd.com> | 2013-09-20 17:34:52 -0400 |
| commit | 0eb3448aa6b31fbf24c31756aba7940cac5ad6b8 (patch) | |
| tree | 0ca178740172d26985af7ddf8325e85a544835be /drivers/gpu/drm/radeon/radeon_ring.c | |
| parent | 42baf21d91d4f52f5b9a4d11dc8e7b1e3b93de7c (diff) | |
drm/radeon: Make r100_cp_ring_info() and radeon_ring_gfx() safe (v2)
Prevent NULL pointer dereference in case when radeon_ring_fini() did it's job.
Reading of r100_cp_ring_info and radeon_ring_gfx debugfs entries will lead to a KP if ring buffer was deallocated, e.g. on failed ring test.
Seen on PA-RISC machine having "radeon: ring test failed (scratch(0x8504)=0xCAFEDEAD)" issue.
v2: agd5f: add some parens around ring->ready check
Signed-off-by: Alex Ivanov <gnidorah@p0n4ik.tk>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Diffstat (limited to 'drivers/gpu/drm/radeon/radeon_ring.c')
| -rw-r--r-- | drivers/gpu/drm/radeon/radeon_ring.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/drivers/gpu/drm/radeon/radeon_ring.c b/drivers/gpu/drm/radeon/radeon_ring.c index 46a25f037b8..18254e1c3e7 100644 --- a/drivers/gpu/drm/radeon/radeon_ring.c +++ b/drivers/gpu/drm/radeon/radeon_ring.c @@ -839,9 +839,11 @@ static int radeon_debugfs_ring_info(struct seq_file *m, void *data) * packet that is the root issue */ i = (ring->rptr + ring->ptr_mask + 1 - 32) & ring->ptr_mask; - for (j = 0; j <= (count + 32); j++) { - seq_printf(m, "r[%5d]=0x%08x\n", i, ring->ring[i]); - i = (i + 1) & ring->ptr_mask; + if (ring->ready) { + for (j = 0; j <= (count + 32); j++) { + seq_printf(m, "r[%5d]=0x%08x\n", i, ring->ring[i]); + i = (i + 1) & ring->ptr_mask; + } } return 0; } |